Vehicle brake mechanism



Re. 17,899 2 Sheets-Sheet N. CHRISTENSEN VEHICLE BRAKE .IEGHANISI Original Filed June 12, 1926 ,0 alt IN V EN TOR.

ATTORNEYS.

N. A. CHRISTENSEN VEHICLE BRAKE HECHANISI 'Re. 17,899 2 Sheets-Sheet 2 Dec. 9, 1930.

Original Filed June 12, 1926 l Illll l ,IIII IIIIIIIII INVENTOR.

AT ORNEYS.

Reissues! Dec. .9, 1930 Re. 17,899 i UNITED STATES 'NIELs A. otanrsrnnsmr, or mm, omo

VEHICLE Basics. MECHANISM Original application filed .Tune 12, 1926, Serial No. 115,804. Renewed May 12,1928. Original No. 1,718,526,

- dated June 25, 1928. Application for reissue filed October 1, 1930. Serial No. 485,786.

The invention relates to brakes for automotive vehicles and trailers'for such vehicles.

1 The object of the invention is to provide a wheel brake mechanism wherein the brake member is a'shoe which is pivotally mounted and en ported adjacent one end upon a linkeral features hereinafter set forth and more particularly defined by claims at the conclusion hereof.

In the drawings Fig. 1 is a sectional view of brake mechanism embodying the invention viewed along the section line 11 of Fig. 2 where said mechanism is shown associated with the front wheel;

Fig. 2 is a section taken on the line 2-2 of Fig 1; i 3 is a detail sectional view taken on the line 3-3 of Fig. 1';

Fig. 4 is a view similar to Fig. 1, showing a modification;

Fi 5 is a detail sectional view taken on 5 the line 55 of Fig. 4;

Fig. 6 is a detail sectional view taken on the line 6-6 of Fig. 4;

Fig. 7 is a detail sectional view taken on the line 7 -7 of Fig. 4. In Figs. 1 to 3 of the drawings the numeral 10 designates the brake drum for-the front wheel, suitably bolted to the hub 11 and spokes 11 of said wheel, the hub being jour-' nailed on the stub axle formed integral with the steering knuckle 12 mounted to swing about the pivot pin13 carried by the front axle 14, and a brake support 15 in the form of a dished plate is secured to a fiat surface 16 of the knuckle by bolts 17.

A pair of brake shoes 18 WOl'k Wlthll'l the drum 10. Each brake shoe is connected to an anchor pin 19'adjacent one end and one end 20 of an anchor pin link 21 is pivotally mounted on a pin 24 fixed to the brake support 15, the bifurcations of one link straddling those of the other link and held against longitudinal movement on the pin by a wash- 'er 23 and bolt 24'. Thus both links21 are mounted on the same supporting pin 24 and each link carries a brake shoe. To limit the swinging movement of the shoe, in its release position, relative to the link, each link has a lug 25 in which a set or stop-screw 26 is mounted which is adapted to engage with a stop lug 27 on the brake support 15 when the shoe is in its release position,said screw 26 being locked in adjusted position by 'a nut 28. To move the lower ends of the shoes to release position a spring 29 is connected at one end to a lug 30 on each link and to an anchor )in 31 on the brake support at its other end. The upper ends of the shoes are moved to release position by a spring 32 connected at its ends to said shoes.

With this construction when the free ends of the shoes are thrust outwardly the shoe will be moved into braking engagement with the drum 10 and owing to the link connection above described, each .shoe moves relative to and with the link so as to bring substan- 8Q tially its entlre braking surface into contact with the drum, and the links are made ver short so as to obtain an eflicient braking e feet. The shoes may be provided with a suitable composition brake lining 33 of metal or 35 friction brake material.

As a means for moving the shoes into engagement with the drum I have shown, in Figs. 1 and 2, a fluid-pressure-operated motor including a brake cylinder 34"having a 00 jack screw 38 has its threaded shank ad-- 'ustably mounted in the free end of each rake shoe and secured by a nut 39 in adjusted position so as to determine the release position of this end of the shoe, and has a flattened head 40 engaging in the slot 7 of the head 36 whereby a thrust connecti n between a moving part of the motor is provided and whereby the shoe is held against lateral movement relative to the drum. The

' brake cylinder 34 is secured by bolts 41 to the support and when a fluid-pressure medium, such ascom' ressed air, is introduced ,fluid-pressure-o The d' erences reside rincipally in into said c linder etween the. istons said pistons wil .move outwardly an thus move said shoes into braking engagement with" said drum in the manner previously described."

.Where 'an increase of braking pressure over that provided by a direct connection between the motor and the shoe is desired, the construction shown in Fi 4 to 7, inclusive, is used. In this construction the brake shoes 18' being similarly anchored and supported as in the first-described construction like reference numerals refer to these parts and the rated motor is also the same. the interposition of a multip ying ever 42 between the head 36 of each piston and an adjustable ack-screw 43 associated with the free end 0 each brake shoe. Each lever 42 is pivotall mounted at one" end upon a pin 44 carried in lugs45 formed integral with the cylinder head 46 of the motor and its free end is flattened to fit into the slot 37 of the head 36 of the piston rod while it has a fiatsided groove 47 intermediate its ends" in which the flattened head 48 of the screw 43 works. Each screw is adjustabl mounted in a split sleeve nut v50 having a t read'edbore 50 and aQwrench-en: head 51 .and an annular groove'52. e shank of said nut fits within-the bore 53 of a split lug portion 54 of the shoe and a clampingbolt 55 extends I through the split portions of said 1 and enga es mthe groove 52 with the t that said It prevents-longitudinal displacement of said not atall tunes andnpon be t tightened u clamps said nut in adj position. us thelooseningof the bolt- 55 permits the sleeve-nut to be turned so that the jack-screw 48 may be moved relative tov the shoe so as to determine'the release position of the free end of'th'e shoe, and each shoe is scan of the brake as the head Q46, so as to move the end of said shoe to a release -tionu n the release Qf flllid'. m the Kit. cylinder. nut -d slots beyond the heads of drum, and means to by a spring with a fixed part and flattened portions of the piston-rod,

levers and screws, the brake shoes are prevented from IDOVIIIfi laterally relative to the drum and are hel tion relative thereto.

in'proper alined posiv The particular association and arrange-.

ment of the lever with a brake member as .above described however forms the subject matter of my id! application Serial 703,952 filed A 13,1924.

With this CQllStI'llCtlOIl the introduction of fluid-pressure between the pistons 35 v I desire it to be understood that this invention is not to be limited to any specific form or arrangement of parts except'in so far as such limitations are specified in the claims.

What I claim as my inventionis:

1. In brake mechanism oi the class de-t scribed, the combination with a rotatable brake, drum, of a brake support, a pin on said support, anchor pin links pivotally mounted on said pin, a pair of brake shoes engageable with the drum, each shoe being connectednear oneend to one of said link s, adjustable means associated with the link-supported end of each shoe to limit its swin ing movement to release position, means actlng on the free ends of said shoes to simultaneously. move them' intobraking engagement with said release said shoes from said drum. A

-2.In brake mechanism of the class. de-. scribed, the combination with a rotatable brake drum, of a brake support, an anchor pin link mounted on said support, a brake shoe engageable with said drum and connected.

adjacent one end to said link, means includ-' ingjan adjustable stop-screw on said'link for limiting the swinging movement of said shoe to a release position, means acting on the free end ofv the shoe to move it into braking en ,gagement with said drum, and means to release'said shoe from said drum.

3; In brake mechanism of the class scribed, the comb" ation with a rotatable brake drum, of a air of brake shoes engagef able with said drum, anchor pin links, each. of said being vrespectively pivotally' I,

connected to one shoe near one end thereof and extending between the ends of said shoes,

a support having a part between the linksupported ends of-said shoes forminga pivotal mounting for said-links, means associated with the link-supported end of each J I shoe to limit its release position, and means for moving said shoes into engagement with said drum. 7

4. In brake mechanism of the class described, the combination with a rotatablebrake drum, of a pair of brake shoes engageable with said drum, anchor pin links,,each of said links being respectively pivotally connected to one. shoe near one end thereof and extending between theends of saidjshoes, a 10 support havin a part between the link-supported ends 0 said shoes forming a pivotal mounting for said links, and means for moving said shoes into engagement with said drum. 15 In testimony whereof, I aflix my signature.

' 'NIELS Ag'OHRISTENSEN. 

